Cooling system for internal-combustion engines



W. W. MUIR April 5, 1927.

COOLING SYSTEM FOR INTERNAL COMBUSTION ENGINES Original Fikged Dec. 9, 1922 W1 "(Muir Aito rzzqy Patented Apr. 5, 1927.

UNITED STATES \VELLING'ION W. MUIR, OF LOCKPOR'I, NEW YORK.

COOLING SYSTEM FOR INTERNAL-COMBUSTION ENGINES.

Application filed December 9, 1922; Serial No. 606,013. Renewed September 18, 1925.

This invention relates to cooling systems for internal combustion engines, and has for its object to provide a system of this character which will be simple in construction, comparatively inexpensive to manufacture, and more etlicient in use than those which have been heretofore proposed.

With these and other objects in view, the invention consists in the novel details of construction and combinations of parts more fully hereinafter disclosed and particularly pointed out in the claims.

Referring to the accompanying drawings forming a part of this specification, in which like numerals designate like parts in all the views:

Figure 1 is an elevational view partially in section of a steam cooling system for internal combustion engines, provided with a pump made in accordance with this invention;

Figure 2 is an elevational view partially in section of a portion of a steam cooling circuit provided with a somewhat modified form of pump venting means; and

Figure 3 is a view similar to Figure 2, showing a still further modified form of pump venting means.

1 indicates any suitable water acket of an internal combustion engine, provided with a pipe 2 extending below the level 3 of the liquid in the jacket 1, and 4: an extension of said pipe leading to the radiator 5 provided with the lower or tank portion 6 and a connection 7 leading to the intake 8 of the pump 9 having the operating shaft 10, the stuffing box 11, and the delivery 12. Said delivery 12 is connected as by the pipe 13, with the jacket 1. and the fluid passing through said pump delivery pipe 13 enters said jacket through the passages la and 15, all as will be clear from the drawings.

The said pump 9 is provided with the impeller blades 16 which by centrifugal action forces the liquid fed by gravity from the tank 6 to their extreme edges 17, thus creating a considerable pressure in the delivery 12 and that portion 18 of the pump adjacent said delivery. This pressure is much greater than is that existing at or near the center portion 19 of said pump, as will be.

readily understood. Further, as will be clear from Figure 1, since the liquid in the jacket is normally maintained at or above its boiling point, more or less vapor accumulates in the space 20, which is liable at times to find its way into the pump, and more or less air existing in the system is of necessity carried over through the pipe 4 and radiator 5 into the tank or space 6, and from there into the pump 9. It is well know that rotary forms of pumps are very desirable for use 'in connection with steam cooling systems for internal combustion engines, and it is also well known that in the ordinary reciprocating type of pump, when air is mixed with the liquid and a greater or less vacuum is produced on the suction stroke, said air rapidly leaves the liquid and tends to fill up the vaccum, so that the pump soon becomes air bound and fails to function properly. In the same way, when a reciprocating pump is handling liquid under pressure and at or above its boiling point, its suction strokes so decrease the pressure on the liquid that the vapor escapes into the vacuum space being produced, and thus again destroys said vacuum in a manner quite similar to the action of air.

It is therefore found in practice to be quite diflicult to satisfactorily handle liquid in cooling systems of this character by means of reciprocating pumps when said liquid is at or above its boiling point. It will be apparent upon reflection that substantially the same remarks apply to centrifugally acting pumps notwithstanding the other advantages they possess unless special precautions are taken to get rid of the air or vapor as fast as it is formed. for it is evident that said. pumps create relatively high pressures on their delivery sides, and relatively low pressures on their suction sides, which tend to cause them to become air bound due to the air seeking the zone of least pressure. And it is further evident that should a cen trifugal pump become clogged up with air, or become air bound, as it is called, the weight of the air being very much less than that of the water, the centrifugal action will cease and the pump will operate unsatisfactorily.

' In this invention, on the other hand these objections are overcome, for when the pres sure of the liquid at the point 18 of the pump exceeds the pressure of the liquid at or near the center 19 of the pump, and the air itself by its own pressure expands towards and fills up the center portion of the pump, it is drawn oil, and thus it is prevented from gradually filling up the pump and preventing the latter from ceasing to operate. That is, I provide the air vent pipe 21, which communicates with the central portion 19 of the pump as at the point 22, and therefore as fast as the air accumulates at said central portion under more or less pressure, said air escapes through the vent 21 into the chamber 23, at the top of the radiator 5, and lifting the valve 24, it escapes to the atmosphere. It thus results that the action of the pump is to gradually eliminate the air from the system, and thus produce an exceedingly certain, smooth working cycle, even thou h the liquid is very hot. The valve 24. automatically seats itself, and therefore when the pressure in the system becomes less than that of the atmosphere, due to the constant elimination otsaid air and the action of the condenser, said valve prevents atmospheric air from entering the system, and thus keeps up the etlicient working of the pump.

In the somewhat modified form of the invention illustrated in Figure 2, the pump 25 is provided with the delivery pipe 26, and

the intake pipe 27, leading from the tank 28 ot' the radiator 29, and from said tank 28 leads the vent pipe 30 provided with the check valve 31, as shown.

In this form of the invention, as in the preceding form, the liquid from the radiator passes from the lower portion thereof, by gravity, into the pump and thus automatically keeps the same primed. But in this particular form, as the liquid is forced to the periphery of the pump blades and creates a pressure in the manner above disclosed, the air which automatically finds itself at the center of the pump passes along the top of the connections or passage 27, back into the receptacle 28 and out the vent tube 30 past the valve 81, to the atmosphere. In this way, the pump 25 automatically trees itself of air in a manner somewhat similar to that disclosed in connection with Figure 1, and thus is it also prevented from becoming air bound.

In the still further modified form of the invention shown in Figure 3, the pump 35 is connected by its passage 27 to the tank 28, ol the radiator 29, and the vent pipe 36 without having any valve leads from the top of said tank 28 to the atmosphere. The de livery side of the pump is provided with the pipe 37, and the air automatically finds itself carried ba k into the tank 28 and out of the vent pipe 36 in a manner similar to that de scribed in connection with Figure 2, and as will be readily understood.

These particular pumps 9, 25 and 35 are each provided with a shaft 10, passing through a single stuliing box 11, and whose ends terminate as at 40, Figure 1, inside the pump chamber. There being only one stui ring box, and the liquid being constantly forced away from the same, the danger of leakage is greatly lessened, and when leakoccurs, the pump still operates satisiactorily.

It will now be clear that in each of the forms of the invention I am enabled to employ a steam space 20 in the jacket, a condenser 5 for the steam; a rotary pump such as 9, a connection such as 7 for automatically keeping said pump primed, a means such as 21. for automatically eliminating air from the rotary pump, and a means such as 2st lior preventing air entering the system alter all the steam therein has been condensed. It

thus results that I am enabled to utilize all the advantages of a centrifugal pump in a steam cooling system without encountering the disadvantages heretofore met with.

't is obvious that those skilled in the art may vary the details of construction, as well as the arrangement and operation of the parts without departing from the spirit of the invention, and therefore, I do not wish to be limited to the above disclosure except as may be required by the claims.

ll hat is claimed is:

1. In a cooling system for internal combastion engines, the combination ot a acket; a radiator connected to said said jacket; a centrifugal pump connected at its central portion to said radiator and at its peripheral portion to said jacket: means associated with said central portion for automatically dra ing" off any air that may accumulate in said pump; and a check valve associated with said last named means to prevent air from returning to the system.

In a cooling system for internal combus'ion engines, the combination of a jacket; a radiator connected to said jacket; a centrit'ugai pump connected at its central portion to said radiator and its peripheral portion to said jacket; means associated with said central portion tor automatically drawoii to the atn'iosphere any air. that may accumulate in said pump and a check valve preventing air from entering said system.

3. In a cooling system for internal combustion engines, the combination ol' a jacket; a radiator connected to said jacket; a centrifugal pump connected at its central portion to said radiator and at its peripheral portion to said jacket; means associated with said central portion and said radiator for auton'latically drawing oil to said radiator any air that may accumulate in said pump; and a check valve carried by said radiator adapted to permit said air to escape to the between the center of said pump and said tank to automatically prime said pump; and valved means joining the central portion of said pump and the top of said radiator adapted to auton'iatically draw oif any air that may accumulate in said pump.

5. In a steam cooling system for internal combustion engines the combination of a jacket provided with a vapor space; a radiator connected with said space and provided with a tank at its bottom; a. centrifugal pump; a horizontally disposed connection between the center of said pump and said tank to automatically prime said pump; and valved means joining the central portion of said pump and the top of said radiator adapted to automatically draw off any air that may accumulate in said pump; and connections between the periphery of said pump and said jacket.

6. The process of forcing hot liquids mixed with air under pressure through the cooling circuits of internal combustion engines and separating the same from said air; which consists in feeding by gravity said air laden liquids into the central portion of a chamber forming a portion of said circuit; creating a higher pressure on said liquids at the outer portions of said chamber than at its central portion whereby said air may accumulate in said central portion; withdrawing said air from said central portion to the atmosphere; preventing additional air entering the system; and conducting said hotliquid under pressure from said outer portions of said chamber through the remaining portions of said circuit.

7. The process of forcing hot liquids mixed with air under pressure through the cooling circuits of internal combustion engines and separating the same from said air. which consists in feeding by gravity said air laden liquids into the central portion of a chamber forming a portion of said circuit: creating by centrifugal action a higher pressure on said liquids at the outer portions of said chamber than at its central portion, whereby said air may through expansion accumulate in said central portion; withdrawing said air from said central portion to the atmosphere while preventing any outside air from entering said chamber; and conducting said hot liquid under pressure from said outer portions of said chamber through the remaining portions of said circuit.

8. The process of eliminating" air from a liquid containing the same in a cooling circuit for internal combustion engines which consists in subjecting said liquid to rotation in a confined space and around a central region while in said circuit to permit said air to expand and collect at said region: drawing off said air from said region to the atmosphere; and preventing additional air from entering the system.

9. In a cooling system for internal combustion engines the combination of a jacket; a radiator connected to said jacket: a centrifugal pump connected on its suction side with said radiator and on its force or delivside with said jacket; and means for automatically venting said pump of any air that may accumulate on the delivery side thereof.

10. In a cooling system for internal com bustion engines the combination of a jacket; a radiator connected to said jacket; a centrifugal pump connected on its suction side with said radiator and on its force or delivery side with said jacket; and a passage connected to the central portion of said pump on the force side thereof and adapted to draw otf any air that may accumulate in said central portion on said delivery side of the pump.

11. In a cooling system for internal combustion engines the con'ibination of a jacket; a radiator connected to said jacket; a centrifugal pump connected on its suction side with said radiator and on its force or delivery side with said jacket; and a )assagc connected to the central portion of said pump on its force side and at the inner boundary of its liquid space adapted to automatically vent to the atmosphere any air present.

In testimony whereof I affix my signature.

WELLINGTON WV. MUIR. 

